The move came after six senators, including five Republicans and one Democrat, announced they would vote against a resolution authorizing the use of force in Syria, a strong indication that the administration's efforts to build bipartisan support have been ineffective.

The Senate was scheduled to vote Wednesday on a procedural motion to begin formal debate on the resolution, but Reid announced late Monday the vote would be delayed in order to buy the president more time to make his case to senators and the public.

"What we need to do is make sure the president has the opportunity to speak to all 100 senators and all 300 million American people before we do this," Reid said, according to USA Today.

The delay came amid reports that Russia was seeking a deal with Syria to dismantle its chemical weapons program. Obama said in television interviews Monday that such a deal could circumvent the need for U.S. military intervention, but senators had not been briefed on the development and expressed skepticism.

"I have no idea what's going on. It'd be great if the Russians could convince Assad to turn over his chemical weapons to the international community. That'd be a terrific outcome. I just am very dubious and skeptical," said Sen. Lindsey Graham, R-S.C.

Earlier on Monday, Russian Foreign Minister Sergei Lavrov called on Bashar Al-Assad’s regime in Syria to give up its chemical weapons stockpile as a way of avoiding military intervention by Western states.

In talks with his counterpart, Syrian Foreign Minister Walid Muallem, Lavrov proposed that Syria's chemical weapons stockpile be placed under "international supervision," following which they would be destroyed. Muallem appeared to back the idea.

In making his suggestion, Lavrov was taking advantage of comments by U.S. Secretary of State John Kerry, who told a press conference in London that Assad could avoid a strike on his country by giving up "every single bit" of his chemical weapons arsenal to the international community within a week.

Kerry later clarified, however, that his comments about Syria were rhetorical and not a proposal.

Kerry’s describing the military effort as "unbelievably small" also rankled lawmakers. Graham, said Kerry, "undercut everything the president has been doing for the last couple of days" to build support.

The rapid clip of senators announcing their opposition on Monday raised serious doubts that the president would be able to muster the necessary support in either the House or Senate, reported USA Today. The GOP-led House is not likely to take up a resolution unless the Senate can pass it first. A final Senate vote was expected this weekend, but Reid's decision to delay the formal debate puts the schedule in flux.

Five GOP Sens. Lamar Alexander of Tennessee, Roy Blunt of Missouri, Johnny Isakson of Georgia, Roger Wicker of Mississippi, and Mike Enzi of Wyoming all announced opposition Monday, as did Democratic Sen. Heidi Heitkamp of North Dakota.

Briefings by top administration officials and a weekend conversation with Secretary of Defense Chuck Hagel were not enough to sway Alexander. "I see too much risk that the strike will do more harm than good by setting off a chain of consequences that could involve American fighting men and women in another long-term Middle East conflict," he said.

Heitkamp was the latest in a string of Democratic senators from conservative states to come out in opposition, including Sen. Joe Manchin, D-W.Va., and Sen. Mark Pryor, D-Ark. Heitkamp and Manchin are working on an alternative resolution that would give the Assad government 45 days to sign an international chemical weapons ban and begin turning over its chemical weapons before authorizing U.S. military action.

Two Democratic senators, Barbara Mikulski of Maryland and Martin Heinrich of New Mexico, declared their support. However, Sen. Ben Cardin, D-Md., who voted for the resolution in the Senate Foreign Affairs Committee, cautioned Monday that he preferred pursuing diplomatic solutions.

Obama will visit Capitol Hill on Tuesday, where he will meet separately with Senate Democrats and Senate Republicans before his prime-time television address.

Graham, who supports the resolution, said he believed it could still pass the Senate. "If the president does a good job tomorrow night, yes," he said.